Development of a multiple-marker RT-PCR assay for detection of micrometastases of hepatocellular carcinoma.

We investigated the expression of several candidate gene markers: MAGE-1, MAGE-3, cytokeratin-20 (CK-20), and alpha-fetoprotein (AFP) in tumor tissue and blood specimens from patients with hepatocellular carcinoma to develop a multiple marker reverse transcriptase-polymerase chain reaction (RT-PCR) assay for detection of micrometastasis in circulation. In 24 tumor specimens, the positivity for MAGE-1, MAGE-3, AFP, and CK-20 genes was 71, 67, 88, and 79% respectively, and all specimens expressed at least one marker. Although AFP and CK-20 transcripts were also detected in corresponding noncancerous liver specimens, none of the 22 corresponding normal specimens or seven normal livers were positive for MAGE-1 or MAGE-3 transcripts. In addition, MAGE-1 and MAGE-3 gene transcripts were not detected in any peripheral blood specimens from 31 normal healthy volunteers. MAGE-1, MAGE-3, and AFP transcripts were detected in 9 (12.7%), 3 (4.8%), and 10 (15.9%) of 71 blood specimens from 11 hepatocellular carcinoma patients, respectively, while 19 specimens (26.8%) were positive for at least one marker. Our results indicate that a multimarker RT-PCR assay with cancer-specific markers such as MAGE-1 and MAGE-3 in combination with a liver-specific AFP marker may be a promising diagnostic tool for monitoring hepatocellular carcinoma patients with better sensitivity and specificity.